fix error messages relating to removing lint for E0276

Author: nikomatsakis

src/test/ui/compare-method/proj-outlives-region.stderr

@@ -1,15 +1,11 @@
-error: impl has stricter requirements than trait
+error[E0276]: impl has stricter requirements than trait
   --> $DIR/proj-outlives-region.rs:19:5
    |
 14 |     fn foo() where T: 'a;
    |     --------------------- definition of `foo` from trait
 ...
 19 |     fn foo() where U: 'a { } //~ ERROR E0276
    |     ^^^^^^^^^^^^^^^^^^^^^^^^ impl has extra requirement `U: 'a`
-   |
-   = note: #[deny(extra_requirement_in_impl)] on by default
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #37166 <https://github.com/rust-lang/rust/issues/37166>
 
 error: aborting due to previous error
 

src/test/ui/compare-method/region-unrelated.stderr

@@ -1,15 +1,11 @@
-error: impl has stricter requirements than trait
+error[E0276]: impl has stricter requirements than trait
   --> $DIR/region-unrelated.rs:19:5
    |
 14 |     fn foo() where T: 'a;
    |     --------------------- definition of `foo` from trait
 ...
 19 |     fn foo() where V: 'a { }
    |     ^^^^^^^^^^^^^^^^^^^^^^^^ impl has extra requirement `V: 'a`
-   |
-   = note: #[deny(extra_requirement_in_impl)] on by default
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #37166 <https://github.com/rust-lang/rust/issues/37166>
 
 error: aborting due to previous error